Apparatus for glazing powder.



PATENTED JULY 14, 1903' A. I. DU FONT. APPARATUS FOR GLAZING POWDER.

APPLICATION FILED FEB. 28, 1903.

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A. I. DU PONT. APPARATUS FOR GLAZING POWDER.

APPLICATION FILE D FEB 28, 1903.

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APPLICATION FILED IB B. 28, 1903. I

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4 SHEETS-SHEET A.

UN TED STATES Patented July 14, 1903.

ALFRED I. DU PONT, OF WILMINGTON, DELAWARE.

APPARATUS FOR GLAZI'NG POWDER.

SPECIFICATION forming part of Letters Patent No. 733,7l2, dated July 14, 1903. Application filed February 28, 1903. $eria1No.145,536. (No model.)

To all. whom it may concern.-

Be it known that I, ALFRED 1.;DU Pour, a citizen of the United States, residing at WVilmington, in the county of Newcastle, State of Delaware,have invented certain new and useful Improvements in Apparatus for Glazing Blasting-Powder, Gunpowder, andthe Like; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and usethe same.

In an application for Letters Patent of the United States, filed of even date herewith, Serial No. 145,535, I have described and claimed certain improvements in the method of glazing blasting and other powders, where by the duration of the operation is radically reduced, the output is increased, the necessary horse-power is materially diminished, the safety factor largely enhanced, and the glazing of very small grains is made entirely feasible.

The present application relates to the apparatus which I prefer to use in practicing the method referred to. v

In the drawings, Figure 1 represents in longitudinal section the main body portion and journals of said apparatus. Fig. 2 represents a like view, on a larger scale, of the steam and air outlet end of the apparatus. Fig. 3 represents an end elevation thereof. Fig. 4 represents in longitudinal section, on a still larger scale, the steam and air inlet end of the apparatus. Fig. 5 represents the inletjoint partly disassembled, and Fig. 6 represents a central transverse section through the drum.

Similar letters of reference indicate similar parts throughout the several views.

Referring to the drawings, it will be noted that the main heads of the apparatus consist of stout castings having inner flanges a a, over which fits the metallic shell A, and having flanges 19 1), against which abut the sheetmetal end plates B O. The castings are provided with central hubs or journals D E, forming journals for the apparatus, which journals are perforated centrally, as shown at (Z d, for a purpose hereinafter to be described.

In order to provide a steam-jacket for the apparatus, I inclose the inner shell A within an outer shell F, said outer shell being centered by means of centering-rings f. The steam-space g thus provided communicates, by means of piping h h, with the steam-channels i z" of the journal D, so that by connecting the said channels to a suitable source of steam-supply a current of steam may be conducted into the steam-space g. At the oppositeend of the drum similar piping h h (see particularly Figs. 2 and 3) conveys the steam from the steam-space g to the outlet-channels 1' of the journalE. The piping k 72, is not shown in Fig. 1, for the reason that it lies in a plane at right angles to the plane in which is located the piping h h, as will be readily understood. I Inorder to permit the drum or barrel and its journals to rotate, while still maintaining steam-tight connection with the steam supply and exhaust conduits, I provide suitable rotatory joints at the ends of the journals D and E.

Therotatory joint connecting the stationary steam-inlet conduit G with the journal D is shown in Figs. 4c and 5. It consists primarily of a plate It, attached to the end of the jourv nal by countersunk screws and connected by bolts and nuts, as shown, to a plate 92, having an air-inlet pipe n registering with and forming a continuation of the channel (I of the journal. Exterior to the plate 11 is a grooved ring-plate r, secured by countersunk screws to the plate 71., thus holding and centel-ing the plates 19 and r. An annular stationary plate 3, having an aperture 8 communicating with the steam-supply conduit G, closes the end of the plate r. It will be evident that in this construction the conduit G, and plate .9 remain stationary, while the re maining parts revolve, a steam-tight connection being constantly maintained and steam being freely supplied to both channels 2%.

At the opposite or exhaust journal-E, I'preferably employ a simpler arrangement, for the reason that the pressure is lower. In this instance (see Figs. 2 and 3) the joint may conveniently consist of a single annular chamber L, secured to the end of the journal'E, seats to revolve therewith, with the exception of the two-part periphery t, which is stationary and within which the circular end walls of the chamber rotate. A stationary collectinghood "0 conveys the exhaust-steam from the annular chamber, which latter is likewise pro vided with a pipe 10, forming a continuation of the outlet-channel cl, which leads from the interior of the barrel or rumble. A lubricatin g-cup supplies oil to the moving surfaces.

The outer shell of the drum or barrel is preferably provided with strengthening T- irons, as shown, and within the steam-jacket are arranged longitudinally thereof the channel-irons :r, whose function is at each revolution of the drum to lift and discharge through the outlet-piping any water of condensation that would otherwise collect in the jacket.

By the construction of apparatus described it is evident that I can maintain a substantially constant temperature within the drum or barrel, the continuously-moving body of steam serving not only to maintain a given temperature within the barrel, but to carry off any excess of temperature which may be generated therein (l uring any stage of the operation.

In the practice of my invention I insert the powder to be glazed within the drum or barrel through the inlet-opening I then close the inlet-opening and rotate the barrel at a speed of about twenty revolutions per minute, at the same time causing a current of steam at a temperature of about 212 Fahrenheit to pass continuously into the steam-space of the rumble and outwardly therefrom. nished by the steam soon raises the temperature of the grains to a point at which the moisture rapidly comes from the interior of the grains to the outer surfaces thereof. \Vhen the temperature of the grains is raised to from 160 to 170 Fahrenheit, moisture equal in amount to about one to three per cent. of their weight comes to the surface of the grains and is given oif in the form of watery vapor. This watery vapor is confined within the interior of the barrel and accumulates in sufficient quantity therein at about the end of threequarters of an hour from the beginning of the rotation of the barrel. Thereupon the admission of steam to the steam-space of the barrel is cut oil and the barrel begins to cool. As the barrel cools the watery vapor within it condenses on the inner surface of the shell A and takes upthe dust produced by the friction of the powder-grains upon each other, thus separating the dust from the grains and depositing it in a layer over the entire inner surface of the rumble. This condensing dustremoving step of the operation requires about one hour or more, at the end of which time the grains are practically clean and a surfaceglaze begins to appear. Cold air may now be circulated through the barrel to drive out any remaining watery vapor, said air entering one of the hollow journals and passing out with the watery vapor through the other. The

circulation of air through the drum is continued until the desired amount of moisture At the proper time pulhas been driven off.

The heat furverized plumbago for polishing the powder is placed in the barrel, and after revolving the barrel for one or more hours longer, depending on the size and kind of powder, the opera tion is completed, the powder-grains being both glazed and dry.

I have already directed attention to the fact that the steam admitted to the jacket during the first hour of the rumbling operation is at boiler-pressure, say 212 Fahrenheit. This is the stage of the rumbling operation during which there is some danger of an excessive rise in temperature beyond the limitations of safety. It is not desirable, however, that the powder-grains should attain too high a temperature, and I find in practice that should the mass of powder approach the temperature of 212 any increase in temperature, due to friction of the grains upon each other, is obviated by reason of the capacity of the steam to conduct away the excess of heat as fast as it is generated. In practice it is found that by using low-pressure steam 210 Fahrenheit is the highest temperature that can be realized within the barrel, this maximum limit serving as an absolute safeguard to the op eration.

At the termination of the operation and after the removal of the glazed grains from the barrel the dust layer deposited upon the inner surface of the barrel is to be removed. This dust layer is of such thickness and solidity as to form a tubular lining to the barrel. A safe and convenient way of removing it consists in readinitting steam into the jacket, thereby causing an expansion thereof sufficient to entirely detach the dust lining. Steam is then admitted into the interior of the dust tube thus detached, so as to soften and break down the arch of the tube. barrel may now be rotated for a few minutes,

whereupon the detached dust lining will break up and will pass through the opening 7a.

Having thus described my invention, what I claim is 1. Apparatus for glazing powder, comprising a revoluble drum having a heating-j aeket, inlet and outlet pipes for said jacket, and retary joints for said inlet and outlet pipes, the inlet-pipes opening into the jacket in a plane transverse to that of the outlet-pipes; substantially as described.

2. Apparatus for glazing powder, eo1nprisin g a revoluble drum having a heating-jacket, inlet and outlet pipes for said jacket, and rotaryijoints for said inlet and outlet pipes, the inlet-pipes opening into the jacket in a plane transverse to that of the outlet-pipes, and a longitudinal partition in the jacket-space for lifting and discharging the water of condensation; substantially as described.

3. Apparatus for glazing powder, comprising a revoluble jacketed drum whose main body portion consists of end or head castings having inwardly projecting flanges upon which fits the inner shell of the drum, and peripheral flanges against'which abut the ends The of the jacket-shell, and angle-rings for holding the j acket-shell in place; substantially as described.

4. Apparatus for glazing powder, comprising a revoluble jacketed drum, whose main body portion'consists of end or head castings having internally projecting flanges upontionary plate having an aperture communia eating with the steam-supply, in combination with a rotatory j oint-plate connected to the inlet-trunnion and having apertures registering with the steam-channels thereof, and rotatory inner and outer ring-plates making steamtight contact with the flanges of the stationary plates; substantially as described.

6. Apparatus for glazing powder, comprisin g a revoluble drum having a heating-jacket, inlet and outlet pipes for said jacket, and r0- tary joints for said inlet and outlet pipes, the rotary inlet-joint comprising a flanged stationary plate having an aperture communicatin g with the steam-supply, in combination with a rotatory joint-plate-connected to the inlet-trunnion and having apertures registering with the steam-channels thereof, and a rotatory plate adjacent to the rotatory j oint-plate and similarly apertured to register with the steam-channels and being furthermore provided with an air-pipe registering with the airchannel of the trunnion; substantially as .de-

rotary joints for said inlet and outlet pipes,

the rotary inlet-joint comprising a flanged stationary plate having an aperture communicating with the steam-supply, in combination with a rotatory joint-plate connected to the inlet-trunnion and having apertures registering with the steam-channels thereof, and a rotatory plate adjacent to the rotatory joint-plate and similarly apertured to register with the steam-channels and being furthermore provided with an air-pipe registering with the air-channel of the trunnion, and an anchorin g-plate apertu red to register with the steam-channels and air-channel, to connect all of the rotatory parts of the joint to the trunnion; substantially as described.

8. Apparatus for glazing powder, comprising a revoluble drum having aheating-jacket, inlet and outlet pipes for said jacket, and rotary joints for said inlet and outlet pipes, the rotary outlet-joint consisting of a shell having a stationary periphery, and having rotatory ends connected to the trunnion and apertured to register with the steam-channels substantially as described.

9. Apparatus for glazing powder, comprisin g a revoluble drum having a heating-jacket, inlet and outlet pipes for said jacket, and rotary joints for said inlet and outlet pipes, the rotary outlet-joint consisting of a shell having a stationary periphery made up of two parts having projecting lugs so that they may be readily assembled, disassembled, or tightened, and having rotatory ends connected to the trunnion and apertured'to register with the steam-channels; substantially as described. y

10. Apparatus for glazing powder, compris inga revoluble drum h aving a heating-j acket, inlet and outlet pipes for said jacket, and rotary joints for said inlet and outlet pipes, the rotary outlet-joint consisting of a shell having a stationary periphery, and having rotatory ends connected to the trunnion and apertured to register with the steam-channels, and having a pipe extension registering with the air-channel; substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

ALFRED I. DU PONT.

Witnesses:

G. A. MADDoX, WM. L. Scorr. 

